[Semifixed] Spectre's Haunt not working correctly

This skill has been ported very incorrectly, with:
Incorrect movespeed when movement speed increasing items are equipped
Incorrect interaction against stuns
Incorrect pathing

Repro:

I am not going to bother with the repro and just show it in a couple of videos.

WC3 Dota:

As you can see the haunt illusion has movespeed increased with items (400 base + 100 BoT's + 10% yasha --> 550, capped at 522)

The illusion is NOT stunned when slardar uses his slithereen crush on it.

The illusion is NOT hindered by terrain or trees, and should walk through furion's sprout too (which I failed to add to the videos)

EDIT: Illusions (Haunt OR Manta etc.) (NOT summons) should also get bonus MS while moving along the dagger's path. (Tested by Appelsin) Non-haunt images will NOT lose their collision from the dagger buff. (i.e. no cliffwalking manta images )

Dota 2:

The haunt illusion's movespeed is 400, regardless of the items it has equipped.

The illusion IS stunned when slardar uses his slithereen crush on it.

The illusion IS hindered by terrain and trees, and fails to walk through things such as sprout by furion

EDIT: Illusions (Haunt OR Manta etc.) do NOT get bonus MS when moving along the dagger's path (Tested by Appelsin)

So basically spec's haunt is broken at the moment, compared to how it used to be for combat purposes, as it's images doesn't move as fast, get hindered by terrain and can be stunned.

EDIT: Thanks to Appelsin for further testing - ALL disables should be ignored, with the EXCEPTION of:

Song of the siren & Nightmare which causes them to get immobilised, but still attack as normal
Hex which acts exactly as you'd expect it to act on an illusion (instant kills it, nothing new here)
Mana drain - instant death to illusions (as always)

Man o man nice find, this is a really big bug you have found here, I can even say critical, imagine how many kills and battles you could have impacted if this worked correctly, like in Dota 1.

I noticed that the ulti is less devastating then in Dota 1 and I couldn't put my finger on it.. I had a suspicion that the MS values are off but didn't think that they freaking ignoring the ms items/auras/terrain/stuns.

Spectre with this bug has missed kills and overall impact in any game he was present, please dev we need a fix for this ASAP.

*Not to mention that I don't like the new weapon and it's also bugged ass hell overlapping old/new weapons, bad bad visual.

I can't believe that the community didn't found this out earlier... the ultimate is broken and in bad bad way.. I'm even thinking on a hotfix for this.

Yeah they shouldn't be stunned unless it's by a channeling disable (dismember/fiends grip)

EDIT: Disregard what I said, all disables should be visual only, and not affect the unit (they keep running through it), with the exception of IMPALE BASED SKILLS, ENSNARE and SONG OF THE SIREN which both immobilise, but don't stop the target from attacking (i.e. they stand there invulnerable, hitting anything near them when affected by SOTS), and IMPALES have full effect.

+1, no wonder why spec seemed like shit in dota 2. is her dispersion also working right? and are u guys sure her haunt illiusions should also have dispersion? cause i thought in dota 1 her dispersion works with her haunt illiusions.

1 other thing I should probably note is that the cliffwalking etc. is very similar to how spectre's dagger used to be - pretty hard to control and only works if you click extremely close together (i.e. won't work on a batrider who's running back and forth over a cliff with firefly). So when implementing this I'm not totally sure how they will go... It will probably seem a little too strong if they make it like a flying unit, and I honestly don't know how you'd meet a middle ground.

Like I said this is major.. imagine if Zeus ultimate only did half damage, basically this is whats happening with Spectre and in some cases in late game (with levels and items,desolate) you will be missing a TON of damage because if this bugs reported here.

Damage that could have made the game swing in your favor. (Huge nerf for Spec in Dota 2 compared to his Dota 1 counterpart)

And about the Dagger, I have made topics and others as well overall the answer was it's "intended", it's nice you don't have to spam shift / right click to walk in different terrains but boy o boy it's a big nerf to Spec if your off the dagger path you instantly lose that phase ability and so your "freedom/juking" is greatly affected not to mention you can get easily stuck and I'm sure you all have experienced it and said is such crap.

Never understood why they can't just make it like in Dota 1 have something like: "If Spectre leaves the dagger path he will have the phase ability buff active still for 6 or 7 seconds". That will make him similar to Dota 1 dagger interactions and maybe they can also give that ability to the illusions from the Haunt ultimate, since they last for 7 sec at lvl 16 and 1 sec delay till they start to hit = making his ulti behave like in the Dota 1 counterpart.